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4 years ago

12

A 500g sample of Potassium-40 is left to decay radioactively. After 3.9 x 109 years, about how many grams of Potassium-40 are ex

pected to remain? [The half-life of Potassium-40 is 1.3 x 109 years.]

2 answers:

ki77a [65]4 years ago

8 0

The answer is 62.5 grams

shusha [124]4 years ago

3 0

It is 62.5g i know for a fact i major and a teacher i'm science and math

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Difference between compound and element?

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Answer: Elements are pure substances which are composed of only one type of atom while compounds are substances which are formed by two or more different types of elements that are united chemically in fixed proportions.

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Answer:

The pressure is $p_1 = 4051.4 \ Pa$

Explanation:

From the question we are told that

The gauge pressure at the mouth is $p_1$

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The speed of the liquid outside the body is $v_2 = 3.1 \ m/s$

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=> $v_ 1 = v_2 * \frac{A_2}{A_1}$

=> $v_ 1 = 3.1 * \frac{1}{10}$

=> $v_ 1 = 0.31 \ m/s$

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=> $r_1 = 10 * r_2$

substituting values

$r_1 = 10 * 0.004$

$r_1 =0.04 \ m$

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Now the height of the column is $h_2 = d = 2r_2 = 2* 0.004 = 0.008\ m$

Generally according to Bernoulli's equation

$p_1 = [\frac{1}{2} \rho v_2^2 + h_2 \rho g +p_2] -[\frac{1}{2} \rho * v_1^2 + h_1 \rho g ]$

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$[(0.5 * 1000 * 0.31^2) + (0.08*1000 * 9.8)]$

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3 years ago

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3 years ago

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Small, slowly moving spherical particles experience a drag force given by Stokes' law: Fd = 6πηrv where r is the radius of the p

Dominik [7]

Answer:

Explanation:

At the time of a body achieving terminal velocity, the drag force becomes equal to the weight of the body less the buoyant force by the surrounding medium which can be represented by the following equation

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3 years ago

Please answer ASAP, and please don't joke around and actually do answer my question. I will give you brainliest if you answer it

hammer [34]

Answer:

30 feet

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First off, if they are throwing at 12.0 m/s and it takes 2.5 seconds. It will be the act of multiplication.

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3 years ago